106 NEW YORK CITY-Meets at 142 E. 40th st., on 1st Wednesday at 10 A. M., 2d Wednesday, at 7% P. M., 4th Monday at 10 A. M., of each month.

N. W. HOLBROOK, C. E., Cor. 43d st., and 4th Avenue, Harlem Engine House.

JAMES BAIRD, F. A. E., Harlem Engine House.

106 BELLOWS FALLS, VT-Meets 1st Thursday and 3d Saturday each month in Gray's Hall, at 8 o'clock P. M.

119 PITTSTON, PA-Meets 1st Sunday at 2 P. M., and 3d Friday eves. in each month, at Engineers' Hall. Address H. H. BROWN, C. E........Lock Box 945 P. H. LAVAN. F. A. E.

120 MOBILE, ALA-Meets 1st and 3d Sundays in each month, at 11 a. m., in Heptasaph's Hall. ......... Whistler, Ala. JAS. HYNDE, C. E,.. Box 298, Mobile, Ala. A. REID, F. A. E........... F. MONTGOMERY, Cor. Sec...........Whistler, ..

135 HUDSON, at JERSEY CITY, N. J.-Meets every Wednesday, over 5th Ward Savings Bank, corner Pavonia avenue and Erie st.

............Erie R'y Eng. House. E. KENT, C. E., W. R. MARTIN, F. A. E., 123 Pavonia Ave.

145, VANDERBILT, at NEW YORK CITYMeets at St. Charles Hall, 8th Ave., between 41st and 42nd Sts., 1st and 3rd Sunday in each month at 1:30 P. M.

M. VOLK, C. E., H. R. & N. Y. C. R. R. Shops, 31st St. and 11th Ave.

N. SAWYER, F. A. E., H. R. & N. Y. C. R. R. Engine House, 45 St. & 4th Ave.

Address G. H. VAN TASSEL, Cor. Sec., 33 Gansevoort St.

W. A. CANFIELD, Journal Ag't, 573, 8th ave. 146, MARSHALLTOWN, IOWA

C. E. BROWN, C. E.

C. F. PETERSON, F. A. E............................................................. Box 174 147, WHEELING, W. VA-Meets in Burk's Hall, Market Square,every Monday eve at 7 P.M. F. H. MORAN, C. E.......... W. N. HENDRIX, F. A. E..

153 PALMETTO, at COLUMBIA, S. C– WM. CAMPBELL, C. E.

J. WILSON, F. A. E., C. C. & A. R. R.

154. HAMPTON, at JUNCTION, N, J.-Meets over Mr, Derea mer's store, on the 1st Sunday of each month, at 2 P. M., and 3d Wednesday at 8 P.M.

EZRA NASON, C. E.

R. W. TAYLOR, F. A. E.

155 DECATUR, ILL-Meets 1st and 3d Saturday of each month in Odd Fellow's building. W. HAYS, C. E.

F. M. HOPEWELL, F. A. E.

156 DANIEL BOONE-At Elizabethtown, Ky, GEO. W. PATRICK, C. E.

Address J. A, SANFORD, F. A. E.

157, CENTRAL DIVISION, at COMMUNIPAW, N. J.-Meets 1st Monday of each Month, a 11 A. M..and 3d Friday, at 7.30 P. M., at Templar's Hall.

C. A. HOUSTON. C. E.. box 47 South Bergen, N.J. C. A. HOWE, F. A. E.,

158 TRUCKEE, AT WADSWORTH, NEV.— ALBERT LYMAN, C. E....

GILBERT LEMERY, F. A. E..

160 CAPITOL, AT WASHINGTON, D. CMeets every 2d and 4th Sundays in each month, at 2 o'clock P. M.

J.LESCALLETT, C. E., B. & P.Station, Washington, D. C.

WM. HARTSHORN, F. A. E., O. A. & M. Station, Alexandria, Va.

161, SAN FRANCISCO, CAL

Address G. W. JOHNSON, Oakland Point, Cal.

12. WILSON, at GREENBUSH, N. Y--Meets 2d and 4th Wednesdays, at Odd Fellows' Hall. W. H. ROBINSON, C. E.

CHAS. MELIUS. F. A. E.

VOL. 7.

ROUND-HOUSE PAPERS-No. II.

BY MONTAGUE.

CHEMICAL AFFINITY.

To one concerned with the mechanic arts, there is no study more interesting, nor, indeed, more important, than chemistry. It is a science founded on practical experiment, proceeding from effect to cause. It deals with nature face to face; wrests from her her most cherished secrets, and lays bare the methods of creation. Winds, rain, change of season, light, heat, motion, decay and reproduction of vegetable life-all are its illustrations. The human body is a most com. plete laboratory of chemical processes; nutrition, digestion, respiration, circulation, waste and supply of tissue-in a word, all the curious functions of animal life obey and illustrate the subtle law of chemical affinity. What then is chemical affinity?

Those of us who have lived longest, and had, as many of us have, a varied experience of human nature, know that it takes "a great many sorts of people to make up a world." No two persons are alike. Some are morose, others gay; some prefer to try the issues of life alone, others seek always to join with kindred spirits in carrying forward the world's enterprises: some persevere with unyielding purpose, others are ever ready to be "off with the old love" and "on with the new."

It is precisely so with the individual in the world of chemistry. Each "element" which goes to make up the substance of created things has peculiar characteristics which distinguish it from other ele

No. 5.

ments, just as men and women are distinguished in the world of humanity. These characteristics enable the skillful chemist to analyze the rocks, soils, ores or other substances, and determine what elements enter into their composition

Let us carry the analogy further. We divide humanity into two great divisions of sex. So we may divide chemical elements into two similar divisions of bases and acids, in which (I hope the ladies will pardon me) the acids correspond with the feminine portion of the human family.

Again, mankind are socially inclined. So with the elements of matter. They are rarely found alone. The divine institution of marriage has been known and practiced in chemical society sinee the world began. The elements do business in partnership, and oxygen has almost as large an interest in chemical combinations as Mr. Co." in the business firms of a great city.

Some elements (and perhaps I should before have defined the word. We mean those substances in which we cannot by any art of analysis detect any other substance in combination, and which we therefore supposed to be pure or elementary)-when brought into proximity, rush into each other's arms with the eagerness of long separated lovers, whilst others cannot be made to combine by the most powerful efforts of science. Others seem diffident and bashful, and if left alone together take a long time to "break the ice" and come to an understanding, though they finally become merged in each other and live devotedly thereafter.

Another class of elements discover so curious a disposition as to merit a special illustration. There is a story of an

Englishman who was standing with some ladies on a wharf by the water's edge, one of whom fell into the water and was in danger of drowning. The cockney, who alone could swim, was besought to spring in and save the drowning fair one. He appeared much distressed, and declared that "nothing would give him more pleasure, but he had never been introduced to her."

Singular as it may appear, some chemical elements are quite as ceremonious. We may rub them together and pound them in a mortar, but, refusing to recognize each other they remain obstinately indifferent. Let a third element, however, be brought in, simply, as it were, to give the others an introduction, and they embrace as lovingly as a young couple in their honeymoon, and lose their identity in each other from that time forth, while the third element takes no part in the resulting combination. But not only in their union do the elements display such close analogy to their human prototypes. Some, when combined, are by the greatest difficulty forced apart. It requires the strong arm of the law, and the stronger arm of the Sheriff's deputy, sometimes, to carry out the judgment of divorce. In other cases, the fickle base (the man, you see, ladies,) at the near approach of a new acid, leaves its loving spouse to shift for itself and takes up all too willingly with the disturber of the domestic peace.

But it often happens, when two compound substances, each consisting of a base and an acid, are brought together, a system of mutual exchange takes place like wife trading between two savages.

From all this the reader will doubtless gather the point of these illustrations, namely, that different elements possess in a most remarkable manner peculiar attachments and aversions for each other. The specific attraction between different kinds of matter, which is the cause of their combination, we call "chemical affinity." Another singular fact in connection is, that the resulting compound possesses properties differing totally from either element of the combination. Still more surprising is the fact that compounds composed of the same elements, but united in different proportions, present wholly different properties. There are many illustrations of this in the nature of paradoxes. Thus carbonic acid is composed of two elements, namely: carbon, which is inflammable, and oxygen, the great supporter of combustion. One would naturally suppose the compound would combine the properties of both elements, and in this case form a most combustible substance. Not so, however. Carbon and oxygen combined, form carbonic acid,

a gas, than which nothing is more deadly to fire. The foul air in mines and deep pits, which is so destructive of life, and extinguishes flame, is composed of it. Yet carbon enters largely into the composition of fuel and of our food; and oxygen is the supporter of combustion and of life.

Take another illustration: Hydrogen, an inflammable gas; oxygen, a supporter of combustion, combined, form water, another deadly enemy to fire.

As an illustration of the different properties possessed by the same elements combined in different proportions, take nitrogen and oxygen-the constituents of the air we breathe. Combine them in a different proportion, and the result is the "laughing gas" now used in dentistry. In still another proportion, they form nitric acid. Other combinations than those above mentioned are well known to the chemist, possessing properties equally various.

The compounds of carbon and oxygen present many illustrations of these facts. Indeed, the whole range of structures formed under the influence of vital force, called organic substances, contain but six of the sixty-five elements known to the chemist. But here we meet with exceptions to the rules of chemical affinity, or rather we perceive the influence of a new force, but little understood, which overrules the ordinary laws of chemical combination. A distinguished chemist has said: "The composition of living tissues cannot be understood. They die the moment chemistry puts her finger upon them. Life is the gift of omnipotence alone. The living frame of the meanest animal or plant is sacred ground, where the chemist can only take the shoes from off his feet and confess the sanctity and inviolability of life."

Without comprehending the nature of vital force we may, however, analyze the substance of animal and vegetable organization, and such analysis has revealed the fact above stated, that it consists of few elements combined in various proportions. Thus carbon, hydrogen and oxygen in combination, produce starch, (including arrow root, tapioca, sago, &c.,) gums, (arabic, tragacanth, &c.,) lignine, (woody fibre, cotton, hemp, &c.,) creosote, paraffine, coal tar, sugar, the many vegetable acids, alcohols, ethers, and the various other vegetable substances, while the introduction of nitrogen and one or two other elements, gives all the constituents of animal structures.

One compound, however, illustrates a most curious fact, namely, that some elements, when brought together in the nascent state, that is, at the moment when

either or both are liberated from some previous combination,-form compounds produced under no other circumstances. Í allude to ammonia, composed of nitrogen and hydrogen, which is formed in the decomposition of organic matter, and to whose presence is largely due the fertilizing property of manures.

Within the brief limits of this article, it is of course impossible to do more than touch upon a few of the salient points illustrating this subject, which forms the basis of chemical knowledge. Almost all the arts and manufactures are but the application of those laws. The iron ore is melted in contact with other substances which have a greater affinity for the foreign elements with which it is associated than the iron itself, and by their union the iron is left in a pure state, fit for various uses. The heat used in the process is but another application of the same laws -indeed, combination, in whatever manner produced, is but an illustration of chemical union, which, scientifically considered, is identical with the rusting of metals and the slow decay of vegetable and animal matter. The rocks, soils, mineral ores, indeed, all the innumerable substances which exist in the earth, air, and water, are composed of a few simple elements, combined by the operation of chemical laws. In another paper it will be our endeavor to trace in a brief survey the mode by which nature effects the chemical changes daily taking place in the world around us, through the instrumentality of those powerful agents, light and heat. These discussions are necessarily fragmentary and imperfect, but if they awaken an interest in the study of the subject among the readers of the JOURNAL, the main object of their prepa ration will have been accomplished.

RAISING WATER.

MESSRS. EDITORS:

Your correspondent, Mr. Hans Voss. merbaumer, wants to know why it is that a pump placed more than 33 feet from the water, will'not raise it if the water is 33 feet below the level of the pump. A common sense view of all things is always the best way of getting at the root of anything that seems beyond our reach, and Mr. Hans Vossmerbaumer has taken that course by asking the question through your valuable JOURNAL.

We will endeavor to enlighten him on the subject by stating, that there is a belt of air around this earth that extends to about 50 miles above the earth and travels with the same velocity that the earth travels, and thus it prevents the inhabitants from flying off in a tangent the same as water flies from a grinding stone when it is run at a high velocity. Now the weight of this air is equivalent to 30 inches of mercury, or 14.7 pounds pressure, which is technically called one atmosphere. Therefore, if we had a tube containing one square inch of area, it would at the level of the sea bear a pressure of 14.7 pounds. And every thing else at the surface of the earth and the level of the sea, sustains a pressure of 147 pounds for each square inch of surface exposed. Now, if Mr. V. H. had a well that was less than 33 feet lower than his pump, he would find that he would first have to remove the air by pumping it out of his pipe. Then as each stroke of the pump removed a portion of the air from the pipe, the water would be pressed up the pipe by the atmosphere equivalent to the quantity of air removed, then it would continue to rise until it had risen to 33.81 feet, and no more, for the simple reason that the pressure of the atmosphere and the weight of water would be just balanced.

But to go a step further, we may say that 2.3 feet of water in an upright pipe will exert a pressure of one inch; if a gauge was placed on a pipe and the pipe was 2.3 feet long above the gauge, it would show one pound pressure, and if it was 4.6 above the gauge it would show two pounds pressure; and so on up to 33.81 feet. But to demonstrate this we will multiply the atmospheric pressure by 2.3 feet and see how near we shall come to the proper height of water for that pressure or the pressure of the atmosphere. Then 2.3 plus 14.7